Facial Nerve Palsy

Question 1

Facial nerve palsy

Answer 1

Examine this patient’s cranial nerves. What is wrong?

Question 2

Clinical signs of Facial nerve palsy

Answer 2

1. Unilateral facial droop, absent nasolabial fold and forehead creases
2. Inability to raise the eyebrows (frontalis), screw the eyes up (orbicularis oculi) or smile (orbicularis oris)
   Bell’s phenomenon: eyeball rolls upwards on attempted eye closure.

Question 3

Level of the lesion:

Answer 3

1. Pons  +VI palsy and long tract signs
⚬⚬ MS and stroke
2. Cerebellar‐pontine angle  +V, VI, VIII and cerebellar signs
⚬⚬ Tumour, e.g. acoustic neuroma
3. Auditory/facial canal  +VIII
⚬⚬ Cholesteatoma and abscess
4. Neck and face  + scars or parotid mass
⚬⚬ Tumour and trauma

Question 4

Commonest cause of Facial nerve palsy

Answer 4

Bell’s palsy

1. Rapid onset (1–2 days)
2. HSV‐1 has been implicated
3. Induced swelling and compression of the nerve within the facial canal causes demyelination and temporary conduction block

Question 5

Treatment of Bell’s palsy

Answer 5

1. Prednisolone commenced within 72 hours of onset improves outcomes, plus aciclovir if severe
2. Remember eye protection (artificial tears, tape eye closed at night)

Question 6

Prognosis of Bell’s palsy

Answer 6

 70–80% make a full recovery; substantial minority have persistent facial weakness

Question 7

Pregnancy and Bell’s palsy

Answer 7

Bell’s palsy is more common in pregnancy, and outcome may be worse.

Question 8

Other causes of a VII nerve palsy

Answer 8

1. Herpes zoster (Ramsay–Hunt syndrome)
2. Mononeuropathy due to diabetes, sarcoidosis or Lyme disease
3. Tumour/trauma
4. MS/stroke

Question 9

Causes of bilateral facial palsy

Answer 9

1. Guillain–Barré
2. Myasthenia gravis
3. Sarcoidosis
4. Bilateral Bell’s palsy
5. Lyme disease